David Gayerie describes an improved method for normal baking, which takes additional model information into account.
I created a Cycles node called Normal to Map to bake normals from material.
When we bake normals using Cycles render engine, normal map and/or bump map are not taken into account. Pretty frustrating because we cannot bake a single normal map from a complex node set.
I wrote an article to explain how you can achieve this using the Normal to Map node and to share the blend file containing that node.